2025/02/15 更新

写真a

フクハラ タケシ
福原 武
所属
理工学術院 大学院先進理工学研究科
職名
教授(任期付)
学位
博士(理学) ( 2009年03月 京都大学 )
ホームページ

経歴

  • 2024年10月
    -
    継続中

    早稲田大学   理工学術院   教授(任期付)

  • 2023年04月
    -
    継続中

    東京理科大学   客員教授

  • 2023年04月
    -
    継続中

    分子科学研究所   客員教授

  • 2022年04月
    -
    継続中

    理化学研究所   量子コンピュータ研究センター   チームリーダー

  • 2022年04月
    -
    2023年03月

    分子科学研究所   客員准教授

  • 2021年04月
    -
    2022年03月

    理化学研究所   量子コンピュータ研究センター   ユニットリーダー

  • 2014年06月
    -
    2021年03月

    理化学研究所   創発物性科学研究センター   ユニットリーダー

  • 2010年06月
    -
    2014年05月

    マックスプランク量子光学研究所   研究員

  • 2009年04月
    -
    2010年05月

    ERATO上田マクロ量子制御プロジェクト   研究員

▼全件表示

委員歴

  • 2022年06月
    -
    継続中

    電子情報通信学会 量子情報技術研究会委員  委員

  • 2022年04月
    -
    継続中

    応用物理学会 量子エレクトロニクス研究会  常任幹事

  • 2020年04月
    -
    2021年03月

    日本物理学会  領域1 運営委員

研究分野

  • 磁性、超伝導、強相関系 / 半導体、光物性、原子物理

研究キーワード

  • 量子シミュレーション

  • 光格子

  • 冷却原子

受賞

  • 文部科学大臣表彰 若手科学者賞

    2017年  

    受賞者: 福原武

  • 日本物理学会若手奨励賞

    2013年  

    受賞者: 福原武

 

論文

  • Observation of chiral-mode domains in a frustrated XY model on optical triangular lattices

    Hideki Ozawa, Ryuta Yamamoto, Takeshi Fukuhara

    Physical Review Research    2023年11月  [査読有り]

    DOI

    Scopus

    2
    被引用数
    (Scopus)
  • Single-site-resolved imaging of ultracold atoms in a triangular optical lattice

    Ryuta Yamamoto, Hideki Ozawa, David C. Nak, Ippei Nakamura, Takeshi Fukuhara

    New Journal of Physics   22 ( 12 ) 123028 - 123028  2020年12月  [査読有り]

    DOI

    Scopus

    21
    被引用数
    (Scopus)
  • Tools for quantum simulation with ultracold atoms in optical lattices

    Florian Schäfer, Takeshi Fukuhara, Seiji Sugawa, Yosuke Takasu, Yoshiro Takahashi

    Nature Reviews Physics   2 ( 8 ) 411 - 425  2020年08月  [査読有り]

    DOI

    Scopus

    280
    被引用数
    (Scopus)
  • Frustrated quantum magnetism with Bose gases in triangular optical lattices at negative absolute temperatures

    Daisuke Yamamoto, Takeshi Fukuhara, Ippei Danshita

    Communications Physics   3 ( 1 )  2020年03月  [査読有り]

     概要を見る

    <title>Abstract</title>Quantum antiferromagnets with geometrical frustration exhibit rich many-body physics but are hard to simulate by means of classical computers. Although quantum-simulation studies for analyzing such systems are thus desirable, they are still limited to high-temperature regions, where interesting quantum effects are smeared out. Here we propose a feasible protocol to perform analog quantum simulation of frustrated antiferromagnetism with strong quantum fluctuations by using ultracold Bose gases in optical lattices at negative absolute temperatures. Specifically, we show from numerical simulations that the time evolution of a negative-temperature state subjected to a slow sweep of the hopping energy simulates quantum phase transitions of a frustrated Bose–Hubbard model with sign-inverted hoppings. Moreover, we quantitatively predict the phase boundary between the frustrated superfluid and Mott-insulator phases for triangular lattices with hopping anisotropy, which serves as a benchmark for quantum simulation.

    DOI

    Scopus

    12
    被引用数
    (Scopus)
  • Non-standard trajectories found by machine learning for evaporative cooling of Rb-87 atoms

    Nakamura Ippei, Kanemura Atsunori, Nakaso Takumi, Yamamoto Ryuta, Fukuhara Takeshi

    OPTICS EXPRESS   27 ( 15 ) 20435 - 20443  2019年07月  [査読有り]

    DOI

    Scopus

    19
    被引用数
    (Scopus)
  • Geometrically frustrated coarsening dynamics in spinor Bose-Fermi mixtures

    Nguyen Thanh Phuc, Momoi, Tsutomu, Furukawa, Shunsuke, Kawaguchi, Yuki, Fukuhara, Takeshi, Ueda, Masahito

    Physical Review a   95 ( 1 ) 013620  2017年  [査読有り]

    DOI

    Scopus

    4
    被引用数
    (Scopus)
  • Spatially Resolved Detection of a Spin-Entanglement Wave in a Bose-Hubbard Chain

    Takeshi Fukuhara, Sebastian Hild, Johannes Zeiher, Peter Schauss, Immanuel Bloch, Manuel Endres, Christian Gross

    PHYSICAL REVIEW LETTERS   115 ( 3 ) 035302  2015年07月  [査読有り]

     概要を見る

    Entanglement is an essential property of quantum many-body systems. However, its local detection is challenging and was so far limited to spin degrees of freedom in ion chains. Here we measure entanglement between the spins of atoms located on two lattice sites in a one-dimensional Bose-Hubbard chain which features both local spin- and particle-number fluctuations. Starting with an initially localized spin impurity, we observe an outwards propagating entanglement wave and show quantitatively how entanglement in the spin sector rapidly decreases with increasing particle-number fluctuations in the chain.

    DOI

    Scopus

    95
    被引用数
    (Scopus)
  • Crystallization in Ising quantum magnets

    P. Schauss, J. Zeiher, T. Fukuhara, S. Hild, M. Cheneau, T. Macri, T. Pohl, I. Bloch, C. Gross

    SCIENCE   347 ( 6229 ) 1455 - 1458  2015年03月  [査読有り]

     概要を見る

    Dominating finite-range interactions in many-body systems can lead to intriguing self-ordered phases of matter. For quantum magnets, Ising models with power-law interactions are among the most elementary systems that support such phases. These models can be implemented by laser coupling ensembles of ultracold atoms to Rydberg states. Here, we report on the experimental preparation of crystalline ground states of such spin systems. We observe a magnetization staircase as a function of the system size and show directly the emergence of crystalline states with vanishing susceptibility. Our results demonstrate the precise control of Rydberg many-body systems and may enable future studies of phase transitions and quantum correlations in interacting quantum magnets.

    DOI

    Scopus

    242
    被引用数
    (Scopus)
  • Far-from-Equilibrium Spin Transport in Heisenberg Quantum Magnets

    Sebastian Hild, Takeshi Fukuhara, Peter Schauss, Johannes Zeiher, Michael Knap, Eugene Demler, Immanuel Bloch, Christian Gross

    PHYSICAL REVIEW LETTERS   113 ( 14 ) 147205  2014年10月  [査読有り]

     概要を見る

    We study experimentally the far-from-equilibrium dynamics in ferromagnetic Heisenberg quantum magnets realized with ultracold atoms in an optical lattice. After controlled imprinting of a spin spiral pattern with an adjustable wave vector, we measure the decay of the initial spin correlations through single-site resolved detection. On the experimentally accessible time scale of several exchange times, we find a profound dependence of the decay rate on the wave vector. In one-dimensional systems, we observe diffusionlike spin transport with a dimensionless diffusion coefficient of 0.22(1). We show how this behavior emerges from the microscopic properties of the closed quantum system. In contrast to the one-dimensional case, our transport measurements for two-dimensional Heisenberg systems indicate anomalous superdiffusion.

    DOI

    Scopus

    185
    被引用数
    (Scopus)
  • Microscopic observation of magnon bound states and their dynamics

    Takeshi Fukuhara, Peter Schauss, Manuel Endres, Sebastian Hild, Marc Cheneau, Immanuel Bloch, Christian Gross

    NATURE   502 ( 7469 ) 76 - +  2013年10月  [査読有り]

     概要を見る

    The existence of bound states of elementary spin waves (magnons) in one-dimensional quantum magnets was predicted almost 80 years ago(1). Identifying signatures of magnon bound states has so far remained the subject of intense theoretical research(2-5), and their detection has proved challenging for experiments. Ultracold atoms offer an ideal setting in which to find such bound states by tracking the spin dynamics with single-spin and single-site resolution(6,7) following a local excitation(8). Here we use in situ correlation measurements to observe two-magnon bound states directly in a one-dimensional Heisenberg spin chain comprising ultracold bosonic atoms in an optical lattice. We observe the quantum dynamics of free and bound magnon states through time-resolved measurements of two spin impurities. The increased effective mass of the compound magnon state results in slower spin dynamics as compared to single-magnon excitations. We also determine the decay time of bound magnons, which is probably limited by scattering on thermal fluctuations in the system. Our results provide a new way of studying fundamental properties of quantum magnets and, more generally, properties of interacting impurities in quantum many-body systems.

    DOI

    Scopus

    366
    被引用数
    (Scopus)
  • Quantum dynamics of a mobile spin impurity

    Takeshi Fukuhara, Adrian Kantian, Manuel Endres, Marc Cheneau, Peter Schauss, Sebastian Hild, David Bellem, Ulrich Schollwoeck, Thierry Giamarchi, Christian Gross, Immanuel Bloch, Stefan Kuhr

    NATURE PHYSICS   9 ( 4 ) 235 - 241  2013年04月  [査読有り]

     概要を見る

    One of the elementary processes in quantum magnetism is the propagation of spin excitations. Here we study the quantum dynamics of a deterministically created spin-impurity atom, as it propagates in a one-dimensional lattice system. We probe the spatial probability distribution of the impurity at different times using single-site-resolved imaging of bosonic atoms in an optical lattice. In the Mott-insulating regime, the quantum-coherent propagation of a magnetic excitation in the Heisenberg model can be observed using a post-selection technique. Extending the study to the superfluid regime of the bath, we quantitatively determine how the bath affects the motion of the impurity, showing evidence of polaronic behaviour. The experimental data agree with theoretical predictions, allowing us to determine the effect of temperature on the impurity motion. Our results provide a new approach to studying quantum magnetism, mobile impurities in quantum fluids and polarons in lattice systems.

    DOI

  • Strongly interacting array of Bose-Einstein condensates trapped in a one-dimensional optical lattice

    Makoto Yamashita, Shinya Kato, Atsushi Yamaguchi, Seiji Sugawa, Takeshi Fukuhara, Satoshi Uetake, Yoshiro Takahashi

    PHYSICAL REVIEW A   87 ( 4 ) 041604(R)  2013年04月  [査読有り]

     概要を見る

    We study a strongly interacting array of Bose-Einstein condensates trapped in a one-dimensional (1D) optical lattice. The system is described by a nonstandard 1D Bose-Hubbard model in which both the tunneling matrix element and the on-site atomic interaction depend on the lattice site due to the interaction broadening of the local wave function and the system inhomogeneity. We quantitatively compare theoretical analyses based on the Gutzwiller approximation with experimental observations obtained using ytterbium atoms. We show that atomic states are highly number squeezed owing to strong interatomic interactions as the lattice potential becomes deeper. Furthermore, the calculated inhomogeneous collisional broadening of spectroscopic line shapes agrees well with high-resolution spectra measured by using the ultranarrow magnetic quadrupole S-1(0)-P-3(2) transition.

    DOI

    Scopus

    7
    被引用数
    (Scopus)
  • Single-site- and single-atom-resolved measurement of correlation functions

    Endres, M., Cheneau, M., Fukuhara, T., Weitenberg, C., Schauss, P., Gross, C., Mazza, L., Banuls, M. C., Pollet, L., Bloch, I., Kuhr, S.

    Applied Physics B-Lasers and Optics   113 ( 1 ) 27 - 39  2013年  [査読有り]

    DOI

    Scopus

    50
    被引用数
    (Scopus)
  • Observation of spatially ordered structures in a two-dimensional Rydberg gas

    Peter Schauss, Marc Cheneau, Manuel Endres, Takeshi Fukuhara, Sebastian Hild, Ahmed Omran, Thomas Pohl, Christian Gross, Stefan Kuhr, Immanuel Bloch

    NATURE   491 ( 7422 ) 87 - 91  2012年11月  [査読有り]

     概要を見る

    The ability to control and tune interactions in ultracold atomic gases has paved the way for the realization of new phases of matter. So far, experiments have achieved a high degree of control over short-range interactions, but the realization of long-range interactions has become a central focus of research because it would open up a new realm of many-body physics. Rydberg atoms are highly suited to this goal because the van der Waals forces between them are many orders of magnitude larger than those between ground-state atoms(1). Consequently, mere laser excitation of ultracold gases can cause strongly correlated many-body states to emerge directly when atoms are transferred to Rydberg states. A key example is a quantum crystal composed of coherent superpositions of different, spatially ordered configurations of collective excitations(2-5). Here we use high-resolution, in situ Rydberg atom imaging to measure directly strong correlations in a laser-excited, two-dimensional atomic Mott insulator(6). The observations reveal the emergence of spatially ordered excitation patterns with random orientation, but well-defined geometry, in the high-density components of the prepared many-body state. Together with a time-resolved analysis, this supports the description of the system in terms of a correlated quantum state of collective excitations delocalized throughout the gas. Our experiment demonstrates the potential of Rydberg gases to realize exotic phases of matter, thereby laying the basis for quantum simulations of quantum magnets with long-range interactions.

    DOI

    Scopus

    457
    被引用数
    (Scopus)
  • The 'Higgs' amplitude mode at the two-dimensional superfluid/Mott insulator transition

    Manuel Endres, Takeshi Fukuhara, David Pekker, Marc Cheneau, Peter Schauss, Christian Gross, Eugene Demler, Stefan Kuhr, Immanuel Bloch

    NATURE   487 ( 7408 ) 454 - U64  2012年07月  [査読有り]

     概要を見る

    Spontaneous symmetry breaking plays a key role in our understanding of nature. In relativistic quantum field theory, a broken continuous symmetry leads to the emergence of two types of fundamental excitation: massless Nambu-Goldstone modes and a massive 'Higgs' amplitude mode. An excitation of Higgs type is of crucial importance in the standard model of elementary particle physics(1), and also appears as a fundamental collective mode in quantum many-body systems(2). Whether such a mode exists in low-dimensional systems as a resonance-like feature, or whether it becomes overdamped through coupling to Nambu-Goldstone modes, has been a subject of debate(2-9). Here we experimentally find and study a Higgs mode in a two-dimensional neutral superfluid close to a quantum phase transition to a Mott insulating phase. We unambiguously identify the mode by observing the expected reduction in frequency of the onset of spectral response when approaching the transition point. In this regime, our system is described by an effective relativistic field theory with a two-component quantum field(2,7), which constitutes a minimal model for spontaneous breaking of a continuous symmetry. Additionally, all microscopic parameters of our system are known from first principles and the resolution of our measurement allows us to detect excited states of the many-body system at the level of individual quasi-particles. This allows for an in-depth study of Higgs excitations that also addresses the consequences of the reduced dimensionality and confinement of the system. Our work constitutes a step towards exploring emergent relativistic models with ultracold atomic gases.

    DOI

    Scopus

    267
    被引用数
    (Scopus)
  • Light-cone-like spreading of correlations in a quantum many-body system

    Marc Cheneau, Peter Barmettler, Dario Poletti, Manuel Endres, Peter Schauss, Takeshi Fukuhara, Christian Gross, Immanuel Bloch, Corinna Kollath, Stefan Kuhr

    NATURE   481 ( 7382 ) 484 - 487  2012年01月  [査読有り]

     概要を見る

    In relativistic quantum field theory, information propagation is bounded by the speed of light. No such limit exists in the non-relativistic case, although in real physical systems, short-range interactions may be expected to restrict the propagation of information to finite velocities. The question of how fast correlations can spread in quantum many-body systems has been long studied(1). The existence of a maximal velocity, known as the Lieb-Robinson bound, has been shown theoretically to exist in several interacting many-body systems (for example, spins on a lattice(2-5))-such systems can be regarded as exhibiting an effective light cone that bounds the propagation speed of correlations. The existence of such a 'speed of light' has profound implications for condensed matter physics and quantum information, but has not been observed experimentally. Here we report the time-resolved detection of propagating correlations in an interacting quantum many-body system. By quenching a one-dimensional quantum gas in an optical lattice, we reveal how quasiparticle pairs transport correlations with a finite velocity across the system, resulting in an effective light cone for the quantum dynamics. Our results open perspectives for understanding the relaxation of closed quantum systems far from equilibrium(6), and for engineering the efficient quantum channels necessary for fast quantum computations(7).

    DOI

    Scopus

    651
    被引用数
    (Scopus)
  • Observation of Correlated Particle-Hole Pairs and String Order in Low-Dimensional Mott Insulators

    M. Endres, M. Cheneau, T. Fukuhara, C. Weitenberg, P. Schauss, C. Gross, L. Mazza, M. C. Banuls, L. Pollet, I. Bloch, S. Kuhr

    SCIENCE   334 ( 6053 ) 200 - 203  2011年10月  [査読有り]

     概要を見る

    Quantum phases of matter are characterized by the underlying correlations of the many-body system. Although this is typically captured by a local order parameter, it has been shown that a broad class of many-body systems possesses a hidden nonlocal order. In the case of bosonic Mott insulators, the ground state properties are governed by quantum fluctuations in the form of correlated particle-hole pairs that lead to the emergence of a nonlocal string order in one dimension. By using high-resolution imaging of low-dimensional quantum gases in an optical lattice, we directly detect these pairs with single-site and single-particle sensitivity and observe string order in the one-dimensional case.

    DOI

    Scopus

    242
    被引用数
    (Scopus)
  • Coherent Light Scattering from a Two-Dimensional Mott Insulator

    Christof Weitenberg, Peter Schauss, Takeshi Fukuhara, Marc Cheneau, Manuel Endres, Immanuel Bloch, Stefan Kuhr

    PHYSICAL REVIEW LETTERS   106 ( 21 ) 215301  2011年05月  [査読有り]

     概要を見る

    We experimentally demonstrate coherent light scattering from an atomic Mott insulator in a two-dimensional lattice. The far-field diffraction pattern of small clouds of a few hundred atoms was imaged while simultaneously laser cooling the atoms with the probe beams. We describe the position of the diffraction peaks and the scaling of the peak parameters by a simple analytic model. In contrast to Bragg scattering, scattering from a single plane yields diffraction peaks for any incidence angle. We demonstrate the feasibility of detecting spin correlations via light scattering by artificially creating a one-dimensional antiferromagnetic order as a density wave and observing the appearance of additional diffraction peaks.

    DOI

    Scopus

    50
    被引用数
    (Scopus)
  • Single-spin addressing in an atomic Mott insulator

    Christof Weitenberg, Manuel Endres, Jacob F. Sherson, Marc Cheneau, Peter Schauss, Takeshi Fukuhara, Immanuel Bloch, Stefan Kuhr

    NATURE   471 ( 7338 ) 319 - +  2011年03月  [査読有り]

     概要を見る

    Ultracold atoms in optical lattices provide a versatile tool with which to investigate fundamental properties of quantum many-body systems. In particular, the high degree of control of experimental parameters has allowed the study of many interesting phenomena, such as quantum phase transitions and quantum spin dynamics. Here we demonstrate how such control can be implemented at the most fundamental level of a single spin at a specific site of an optical lattice. Using a tightly focused laser beam together with a microwave field, we were able to flip the spin of individual atoms in a Mott insulator with sub-diffraction-limited resolution, well below the lattice spacing. The Mott insulator provided us with a large two-dimensional array of perfectly arranged atoms, in which we created arbitrary spin patterns by sequentially addressing selected lattice sites after freezing out the atom distribution. We directly monitored the tunnelling quantum dynamics of single atoms in the lattice prepared along a single line, and observed that our addressing scheme leaves the atoms in the motional ground state. The results should enable studies of entropy transport and the quantum dynamics of spin impurities, the implementation of novel cooling schemes, and the engineering of quantum many-body phases and various quantum information processing applications.

    DOI

    Scopus

    581
    被引用数
    (Scopus)
  • Quadrupole oscillations in a quantum degenerate Bose-Fermi mixture

    Fukuhara, T., Tsujimoto, T., Takahashi, Y.

    Applied Physics B-Lasers and Optics   96 ( 2-3 ) 271 - 274  2009年08月  [査読有り]

    DOI J-GLOBAL

    Scopus

    10
    被引用数
    (Scopus)
  • Mott insulator of ultracold alkaline-earth-metal-like atoms

    Takeshi Fukuhara, Seiji Sugawa, Masahito Sugimoto, Shintaro Taie, Yoshiro Takahashi

    PHYSICAL REVIEW A   79 ( 4 ) 041604(R)  2009年04月  [査読有り]

     概要を見る

    The transition from a superfluid to a Mott-insulator (MI) phase has been observed in a Bose-Einstein condensate (BEC) of ytterbium (Yb) atoms in an optical lattice. An all-optically produced BEC of (174)Yb atoms was loaded into three-dimensional optical lattices produced by a 532 nm laser beam. The interference pattern was measured after releasing the quantum gas from the trapping potential. As increasing the optical lattice depth, we observed the disappearance of the interference patterns, which is a signature of entering the MI regime. This result is an important step into studies by using a combination of the MI state and the ultranarrow optical transition of ultracold alkaline-earth-metal-like atoms.

    DOI

    Scopus

    66
    被引用数
    (Scopus)
  • All-optical formation of quantum degenerate mixtures

    Takeshi Fukuhara, Seiji Sugawa, Yosuke Takasu, Yoshiro Takahashi

    Physical Review A - Atomic, Molecular, and Optical Physics   79 ( 2 ) 021601(R)  2009年02月  [査読有り]

     概要を見る

    We report the realization of quantum degenerate mixed gases of ytterbium (Yb) isotopes using all-optical methods. We have succeeded in cooling attractively interacting Yb176 atoms via sympathetic cooling down to below the Bose-Einstein transition temperature, coexisting with a stable condensate of Yb174 atoms with a repulsive interaction. We have observed a rapid atom loss in Yb176 atoms after cooling down below the transition temperature, which indicates the collapse of a Yb176 condensate. The sympathetic cooling technique has been applied to cool a Yb173 - Yb174 Fermi-Bose mixture to the quantum degenerate regime. © 2009 The American Physical Society.

    DOI

    Scopus

    113
    被引用数
    (Scopus)
  • Bose-Einstein condensation of an ytterbium isotope

    Takeshi Fukuhara, Seiji Sugawa, Yoshiro Takahashi

    PHYSICAL REVIEW A   76 ( 5 ) 051604(R)  2007年11月  [査読有り]

     概要を見る

    We report the observation of a Bose-Einstein condensate in a bosonic isotope of ytterbium ((170)Yb). More than 10(6) atoms are trapped in a crossed optical dipole trap and cooled by evaporation. Condensates of approximately 10(4) atoms have been obtained. From an expansion of the condensate, we have extracted the scattering length a(170)=3.6 +/- 0.9 nm.

    DOI

    Scopus

    112
    被引用数
    (Scopus)
  • Quantum degenerate fermi gases of ytterbium atoms

    T. Fukuhara, Y. Takasu, S. Sugawa, Y. Takahashi

    Journal of Low Temperature Physics   148 ( 3-4 ) 441 - 445  2007年  [査読有り]

    DOI

    Scopus

    11
    被引用数
    (Scopus)
  • Degenerate fermi gases of ytterbium

    Takeshi Fukuhara, Yosuke Takasu, Mitsutaka Kumakura, Yoshiro Takahashi

    PHYSICAL REVIEW LETTERS   98 ( 3 ) 030401  2007年01月  [査読有り]

     概要を見る

    Evaporative cooling was performed to cool fermionic Yb-173 atoms in a crossed optical dipole trap. The large elastic collision rate leads to efficient evaporation and we have successfully cooled the atoms to 0.37 +/- 0.06 of the Fermi temperature, that is to say, to a quantum degenerate regime. In this regime, a plunge of evaporation efficiency was observed as a result of Fermi degeneracy.

    DOI

    Scopus

    278
    被引用数
    (Scopus)
  • Quantum-degenerate gases of Ytterbium atoms

    Y. Takasu, T. Fukuhara, M. Kitagawa, M. Kumakura, Y. Takahashi

    Laser Physics   16 ( 4 ) 713 - 717  2006年  [査読有り]

    DOI

    Scopus

    5
    被引用数
    (Scopus)

▼全件表示

共同研究・競争的資金等の研究課題

  • カゴメ格子量子気体顕微鏡による量子スピン液体の研究

    日本学術振興会  科学研究費助成事業

    研究期間:

    2019年04月
    -
    2022年03月
     

    福原 武

     概要を見る

    カゴメ格子の基本的な構造となる三角格子において、極低温原子気体を単一格子・単一原子レベルで測定することに世界で初めて成功した。また、量子気体(ボース・アインシュタイン凝縮体)を生成し、三角光格子に導入することで超流動-モット絶縁体の量子相転移の観測にも成功した。その際に、トラップ中での飛行時間測定法を行うことで、量子気体顕微鏡を用いた運動量分布の測定が可能であることも実証できた。更に、光格子の位相を変調することで格子間トンネリングの符号を反転させるフロケ制御も実装した。負のトンネリングは反強磁性結合となるので、これによりフラストレートした量子スピン系の研究を行う準備ができた。

Misc

  • 光格子を用いた量子シミュレーション

    福原武

    パリティ 2018年5月号     4 - 12  2018年04月  [招待有り]

  • ベイズ最適化に基づく冷却原子実験におけるパラメータ探索の効率化

    中村一平, 兼村厚範, 中曽拓, 山本隆太, 福原武

    日本物理学会講演概要集(CD-ROM)   73 ( 1 ) 692 - 692  2018年

    DOI CiNii J-GLOBAL

  • Frustrated Spin Dynamics in Spinor Bose-Fermi Mixtures

    Phuc Nguyen Thanh, Momoi Tsutomu, Furukawa Shunsuke, Kawaguchi Yuki, Fukuhara Takeshi, Ueda Masahito

    日本物理学会講演概要集   71   490 - 490  2016年

     概要を見る

    <p>When magnetic interactions are incommensurate with the underlying lattice geometry, exotic frustration phenomena such as spin ice and spin liquids may emerge. We show that mixtures of bosonic and fermionic atoms can be used to study the real-time dynamics of a frustrated spin system in which a long-range spin-exchange interaction is induced through the fermionic medium and amplified by bosonic enhancement. The geometrical frustration is shown to hinder the magnon propagation and the growth of spin-chirality correlation and to create unconventional SO(3) vortices in triangular and kagome lattices. In particular, various long-time correlation lengths and the vortex density are found to scale with the degree of frustration.</p>

    DOI CiNii

  • 9aAW-13 光格子系におけるエンタングルメントの動的な生成(9aAW 量子エレクトロニクス(冷却原子,量子縮退原子),領域1(原子分子・量子エレクトロニクス・放射線))

    福原 武, Hild Sebastian, Zeiher Johannes, SchauB Peter, Endres Manuel, Gross Christian, Bloch Immanuel

    日本物理学会講演概要集   69 ( 2 ) 82 - 82  2014年08月

    CiNii

  • 27pEE-7 Quantum dynamics of a single, mobile spin impurity

    Fukuhara T., Kantian A., Endres M., Cheneau M., Schauss P., Hild S., Bellem D., Schollwock U., Giamarchi T., Gross C., Bloch I., Kuhr S.

    日本物理学会講演概要集   68 ( 1 ) 221 - 221  2013年03月

    CiNii

  • 27aED-3 多様な量子縮退原子気体、特に超低温多成分フェルミ原子気体の実現(27aED 領域1若手奨励賞記念講演,領域1(原子・分子,量子エレクトロニクス,放射線物理))

    福原 武

    日本物理学会講演概要集   68 ( 1 ) 209 - 209  2013年03月

    CiNii

  • Quantum dynamics of a single, mobile spin impurity

    Takeshi Fukuhara, Adrian Kantian, Manuel Endres, Marc Cheneau, Peter Schauss, Sebastian Hild, David Bellem, Ulrich Schollwoeck, Thierry Giamarchi, Christian Gross, Immanuel Bloch, Stefan Kuhr

    2013 CONFERENCE ON LASERS AND ELECTRO-OPTICS (CLEO)    2013年  [査読有り]

  • 30pSD-7 量子縮退Yb原子の光格子実験III(30pSD 量子エレクトロニクス(量子縮退原子気体),領域1(原子・分子,量子エレクトロニクス,放射線物理))

    素川 靖司, 福原 武, 杉本 昌仁, 田家 慎太郎, 植竹 智, 垣内 久, 高橋 義朗

    日本物理学会講演概要集   64 ( 1 ) 187 - 187  2009年03月

    CiNii

  • 30pSD-6 量子縮退Yb原子の光格子実験II(30pSD 量子エレクトロニクス(量子縮退原子気体),領域1(原子・分子,量子エレクトロニクス,放射線物理))

    田家 慎太郎, 福原 武, 素川 靖司, 杉本 昌仁, 高橋 義朗

    日本物理学会講演概要集   64 ( 1 ) 187 - 187  2009年03月

    CiNii

  • 28aSL-12 一次元光格子にトラップされた^<174>Ybボース凝縮体アレイの数値解析(28aSL 量子エレクトロニクス(Fermi粒子系,及びBose粒子系の理論),領域1(原子・分子,量子エレクトロニクス,放射線物理))

    山下 眞, 山口 敦史, 素川 靖司, 福原 武, 植竹 智, 高橋 義朗

    日本物理学会講演概要集   64 ( 1 ) 157 - 157  2009年03月

    CiNii

  • 25pQD-12 Yb原子の光格子実験(量子エレクトロニクス(量子縮退気体(実験),原子の冷却・トラップ),領域1,原子・分子,量子エレクトロニクス,放射線物理)

    素川 靖司, 福原 武, 杉本 昌仁, 田家 慎太郎, 高須 洋介, 高橋 義朗

    日本物理学会講演概要集   63 ( 1 ) 188 - 188  2008年02月

    CiNii

  • Quantum degenerate gases and the mixtures of ytterbium atoms

    T. Fukuhara, S. Sugawa, Y. Takasu, Y. Takahashi

    Ultracold Fermi Gases, Proceedings of the International School of Physics "Enrico Fermi"   164   857 - 866  2008年  [招待有り]

  • 24pRH-5 冷却Yb原子^1S_0-^3P_0遷移の高分解能分光II(量子エレクトロニクス(原子の冷却・トラップ),領域1,原子・分子,量子エレクトロニクス,放射線物理)

    植竹 智, 山口 敦史, 加藤 真也, 福原 武, 李 瑛, 細川 瑞彦, 高橋 義朗

    日本物理学会講演概要集   62 ( 2 ) 204 - 204  2007年08月

    CiNii

  • 24pRH-6 Ybボース・フェルミ混合系における集団振動(量子エレクトロニクス(原子の冷却・トラップ),領域1,原子・分子,量子エレクトロニクス,放射線物理)

    福原 武, 辻本 拓也, 素川 靖司, 高須 洋介, 高橋 義朗

    日本物理学会講演概要集   62 ( 2 ) 205 - 205  2007年08月

    CiNii

  • 20aXK-2 スピン偏極によるYbフェルミ原子冷却の最適化(量子エレクトロニクス(冷却原子実験),領域1,原子・分子,量子エレクトロニクス,放射線物理)

    福原 武, 素川 靖司, 高橋 義朗

    日本物理学会講演概要集   62 ( 1 ) 156 - 156  2007年02月

    CiNii

  • 24aRB-7 Yb原子の混合量子縮退(24aRB 量子エレクトロニクス(原子のBEC・冷却原子実験),領域1(原子・分子,量子エレクトロニクス,放射線物理))

    福原 武, 素川 靖司, 高須 洋介, 高橋 義朗

    日本物理学会講演概要集   61 ( 2 ) 95 - 95  2006年08月

    CiNii

  • 24aRB-6 ^<170>Yb原子のボース・アインシュタイン凝縮の実現(24aRB 量子エレクトロニクス(原子のBEC・冷却原子実験),領域1(原子・分子,量子エレクトロニクス,放射線物理))

    素川 靖司, 福原 武, 高須 洋介, 高橋 義朗

    日本物理学会講演概要集   61 ( 2 ) 94 - 94  2006年08月

    CiNii

  • 29pTA-4 Yb原子のフェルミ縮退に向けた冷却II(29pTA 量子エレクトロニクス(レーザー冷却・BEC実験),領域1(原子・分子,量子エレクトロニクス,放射線物理))

    福原 武, 高須 洋介, Wasan Ajay, 熊倉 光孝, 高橋 義朗

    日本物理学会講演概要集   61 ( 1 ) 171 - 171  2006年03月

    CiNii

  • 19aWA-9 ^<172>Ybおよび^<176>Yb原子のボーズ凝縮実現に向けた蒸発冷却II(量子エレクトロニクス(冷却原子実験・BEC理論),領域1(原子・分子,量子エレクトロニクス,放射線物理))

    高須 洋介, 福原 武, 熊倉 光孝, 高橋 義朗

    日本物理学会講演概要集   60 ( 2 ) 45 - 45  2005年08月

    CiNii

  • 19aWA-8 Yb原子のフェルミ縮退に向けた冷却(量子エレクトロニクス(冷却原子実験・BEC理論),領域1(原子・分子,量子エレクトロニクス,放射線物理))

    福原 武, 高須 洋介, 熊倉 光孝, 高橋 義朗

    日本物理学会講演概要集   60 ( 2 ) 44 - 44  2005年08月

    CiNii

  • 26pYE-11 光格子中の冷却Yb原子II(量子エレクトロニクス(レーザー冷却),領域1(原子・分子,量子エレクトロニクス,放射線物理))

    福原 武, 北川 昌明, 高須 洋介, 熊倉 光孝, 高橋 義朗

    日本物理学会講演概要集   60 ( 1 ) 168 - 168  2005年03月

    CiNii

  • 27aXG-3 <87>^Rbボース凝縮体における磁場反転による高次量子渦の生成(量子エレクトロニクス(冷却・実験))(領域1)

    廣谷 太志, 福原 武, 小林 淳, 熊倉 光孝, 高橋 義朗, 薮崎 努

    日本物理学会講演概要集   59 ( 1 ) 142 - 142  2004年03月

    CiNii

▼全件表示

 

現在担当している科目

▼全件表示

 

他学部・他研究科等兼任情報

  • 理工学術院   先進理工学部